A study of the brightness of laryngoscope light

Anaesthesia. 1996 Jul;51(7):667-72. doi: 10.1111/j.1365-2044.1996.tb07851.x.

Abstract

We have measured the brightness (luminance) of the light spot produced by 105 Macintosh 3 laryngoscope blades (33 bulb, 72 fibrelight) using a Hagner photometer. An estimate of the minimum luminance required for laryngoscopy (circa. 100 cd.m-2), was determined using a laryngoscope adapted to provide a variable light output. Five (15%) of bulb blades and 24 (33%) of the fibrelight blades failed to meet this minimum level. A new bulb blade produced brighter lighting conditions (maximum 700 cd.m-2) than a new fibrelight blade (max. 500 cd.m-2). In total, 61 (84%) of the fibrelight blades and three (9%) of the bulb blades were found to provide a light spot that encompassed areas of luminance below 30 cd.m-2, which is a level for comfortable reading. The light spot from a mains-powered fibreoptic bronchoscope was found to be four times brighter (2000 cd.m-2) than a new battery-powered fibrelight laryngoscope.

Publication types

  • Comparative Study

MeSH terms

  • Bronchoscopes
  • Fiber Optic Technology / instrumentation
  • Humans
  • Laryngoscopes*
  • Lighting*
  • Photometry